Water Quality Analysis
Chemical Additives 2025-03-18
Water Quality Analysis: Comprehensive Technical Overview
1. Definition & Purpose
Water quality analysis is a systematic evaluation of physical, chemical, and biological parameters to determine water safety and usability. It supports:
- Public health protection (drinking water compliance)
- Ecosystem monitoring (aquatic life preservation)
- Pollution source tracking (industrial/agricultural runoff)
2. Key Parameters & Testing Methods
| Category | Parameters | Standard Methods | Target Values (WHO/EPA) |
|---|---|---|---|
| Physical | Turbidity, Color, Temperature | ASTM D1889 (Turbidity) | Turbidity <1 NTU (drinking) |
| Chemical | pH, DO, BOD, COD, Heavy Metals | EPA 200.7 (Metals), APHA 4500 (BOD) | pH 6.5–8.5; Pb <0.01 mg/L |
| Biological | E. coli, Coliforms, Algae | ISO 9308-1 (Bacteria), EPA 440.4 | 0 CFU/100mL (E. coli, drinking) |
| Nutrients | Nitrates, Phosphates | APHA 4500-NO₃ (Nitrates) | NO₃⁻ <50 mg/L (WHO) |
3. Sampling & Analysis Workflow
- Sampling:
- Follow ISO 5667 protocols (clean containers, preservatives).
- Types: Grab (spot) vs. Composite (time/flow-weighted).
- Field Tests:
- Portable meters for pH, DO, conductivity.
- Lab Analysis:
- Spectroscopy (ICP-OES for metals).
- Chromatography (HPLC for pesticides).
- Microbiology (membrane filtration for bacteria).
4. Applications by Water Source
| Source | Priority Tests | Common Issues |
|---|---|---|
| Drinking Water | Pathogens, Chlorine, Lead | Disinfection byproducts (THMs) |
| Surface Water | BOD, Algae, Pesticides | Eutrophication (high phosphates) |
| Groundwater | Nitrates, Arsenic, VOCs | Industrial contamination |
| Wastewater | COD, TSS, Oil/Grease | Heavy metals (e.g., Hg, Cd) |
